T square guide



Oct. 7, 195 8 H. J. CASEY, JR

'1 SQUARE GUIDE Filed Oct. 5, 1953 40 F i'g. 3

/5 Fig. 2

I- l I I I I V i Harold J. Casey, Jr:

IN VEN TOR.

- 1 BY w United States Patent 1 2,854,751 T SQUARE GUIDE Harold J. Casey, Jr., Schenectady, N. Y. Application October 5, 1953, Serial No. 384,139 1 Claim. (Cl. 33-80) This invention relates to a T square guide and more specifically provides an attachment for the blade of a T square for retaining the T square in position on a drawing board or other supporting surface while the drawing board is in a vertical or substantially vertical position.

An object of this invention is to provide a T square guide which is attached to a blade of a T square wherein the T square and guide is resiliently held onto a supporting surface such as a drawing board.

A further object of this invention is to provide a T square guide for resiliently holding a T square on a drawing board wherein the guide is provided with adjustable resilient means for maintaining the T square on the board.

Another object of this invention is to provide a T square guide which is slidably attached to a blade of a T square for holding the T square on a drawing board while the drawing board is in an upright or substantially vertical position.

Yet another object of this invention is to provide a T square guide which is simple in construction, easy to manipulate and inexpensive to manufacture.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure l is a perspective view of the T square guide of this invention in operative position on the T square and engaging the side edge of a drawing board;

Figure 2 is a longitudinal, vertical section taken substantially along the center line of the coil spring and coil spring adjusting means;

Figure 3 is a longitudinal, vertical section taken substantially along the center line of one of the valve guide means;

Figure 4 is a bottom view showing the attaching screws which secure the guide to the blade of the T square; and,

Figure 5 is a top plan View showing the general relationship of the drawing board, T square and T square guide.

Referring now more specifically to the drawings and especially to Figure 5, it will be seen that the T square guide of this invention is generally designated by the numeral i and is attached to the blade T41 of a T square having the usual head 14 and adapted to fit upon a conventional drawing board 16.

The T square guide of this invention is attached to the blade 12.at its end remote from the T square head 14. The T square guide includes a block 18 secured to the upper surface of the blade 12 by suitable fastening screws 20 and the body of the block 18 is provided with a centrally located or intermediate longitudinal bore or socket 22 projecting inwardly from one edge of the block 18 and ending adjacent the midpoint thereof. A coil spring 24 is disposed in the bore 22 with said spring 24 having looped end portions 26 and a spring pin 28 is disposed across the bore 22 and through the loop portion 26 of spring 24. A slide member 30 having a central or intermediate bore 32 therein is positioned in alignment with the bore 22 and the opposite end of coil spring 24 is disposed therein. A threaded member or shank 34 has an apertured end portion which 2,854,751 Patented Oct. 7, 1958 is engaged by the looped end portion 26 of spring 24 and a knurled nut 36 is threaded on the threaded member 34 and engages a washer 38 which abuts the outer edge of the slide member 30 adjusting the tension of spring 24 when the slide is in position around the edge of the drawing board 16. In the block 18, a pair of outer sockets or bores 40 having dowels 42 fixed therein and projecting outwardly therefrom on each side of coil spring 24 and the slide member 30 is provided with complementary outer bores 44 for slidably receiving the projecting portions of the dowels 42 thereby providing guides for sliding the slide 30 in relation to the block 18 due to the action of the coil spring 24. As best seen in Figure 2 the slide 30 has a substantially channel shaped recess 46 which has an inwardly projecting lip 48 along the undersurface thereof to be disposed under the edge of the drawing board 16. Further, the channel shaped recess 46 has a generally smooth curve 50 joining its outer edge with its inner surface thereby providing a smooth sliding fit with the edge of the drawing board 16.

The operation of the device will be readily understood. With the T square guide 10 on the T square 12 the head of the T square is placed on the one edge of the drawing board 16 and the slide 30 is pulled outwardly thereby stretching the tension spring 24 and allowing the lip member 48 to be passed under the drawing board 16 and the recess portion 46 engaging the edge of the drawing board 16. Obviously, the tension of spring 24 may be adjusted by manipulating the knurled nut 36 and the T square may be secured in one position or moved along the edge of the drawing board as desired by the draftsman. The device may be made of any suitable material such as wood or plastic which are readily available.

From the foregoing, the construction and operation of the device will be readily understood and further explanation is believed to be unnecessary. However, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the appended claim.

What is claimed as new is as follows:

A guide for a T-square having a blade, said'guide comprising: a substantially flat block fixed on the free end portion of the blade and having a socket extending thereinto from the outer end thereof and paralleling the blade, a pair of spaced, parallel guide pins projecting from said outer end of said block on opposite sides of the socket, a transversely elongated member mounted for reciprocation on the pins and slidably engageable with an edge of a drawing board on which the T-s'quare is being used, said member having a bore therein aligned with the socket, a threaded shank in the bore, a coil spring anchored in the socket and connected to the shank for yieldingly' engaging the member with the board, and an adjustable anchoring nut threaded on the shank and engaged with said member.

References Cited inthe file of this patent UNITED STATES PATENTS 977,765 White Dec. 6, 1910 2,261,055 Dulaney Oct. 28, 1941 2,370,470 Joss Feb. 27, 1945 FOREIGN PATENTS 336,866 Germany May 18, 1921 346,794 Germany Jan. 7, 1922 226,989 Great Britain Jan. 8, 1925 

